Compensating air-pump for pneumatic vehicle-wheels.



H. -C. SCHROEDER. COMPENSATING AIR PUMP FOR PNEUMATIC VEHICLE WHEELS.

APPLICATION FILED mus. ms.

1,285,808. atented Nov. 26, 1918.

HARRY C. CHROEDEB, OF BERKELEY, CALIFORNIA.

COMPENSATING AIR-PUMP FOR PNEUMATIC VEHICLE-WHEELS.

Specification of Letters Patent.

Patented Nov. 26, 1918.

Application filed January 3, 1918. Serial No. 210,198.

To all whom it may concern:

Be it known that I, HARRY C. Scnxononn, citizen of the United States,residing at Berkeley, in the county of Alameda and State of California,have invented certain new and useful Im rovements in CompensatingAir-Pumps or Pneumatic Vehicle- Wheels, of which the following is aspecification.

My invention is a compensating air pump for neumatic vehicle tires.

re particularly my invention contemplates a pump of this type arrangedentirely within the cap of the tire valve.

The figure in the drawing is a longltudinal section of my inventionattached to the valve of a pneumatic tire.

In the drawing 1 indicates the valve of a pneumatic tire and 2 the captherefor. The cap 2 is formed with an internally threaded internalflange 3 which screws onto the tire valve nipple 4. The outer end of thecap 2 is provided with an inlet port 5. A head 6 is arranged in theouter end of the cap which head is provided with an inlet port 7controlled by an inlet valve 8. A head 9 is arranged within the cap nearits inner end which head rests over the valve nipple in engagement witha washer 10 on top of the nipple. Said head is provided wlth a port 12controlled by a valve 13, which ort communicates with the valve 1. A he14 is arranged above the head 9 in the cap 2,

- providing an airreservoir 15 between said heads, from which reservoirthe port 12 leads. A weighted head 16 is arranged to reciprocate in thecap between the heads 14 and 6. A diaphragm or bellows 17 is interposedbetween the head 6 and the weighted head 16 and forms an air inletchamber 18. A diaphragm or bellows 19 is interposed between the head 14and the weighted head 16 and forms a compression chamber 20. Theweighted head 16 is rovided with a port 21 leading from the air inletchamber 18 into the air compression chamber 20, which port is controlledby a valve 22. .'I he head 14 is provided'with a port 23 leading 'fromthe compression chamber 20 to the reservoir 15, which port is controlledby a valve 24. A packin 25 is interposed between the head 6 an the outerend of the cap 2 through which packing air maydpass from the port 5 tothe port 7 as deslre The to 26 of the cap 2 screws into the upper en ofthe body of the cap and may be screwed oil the cap body for assemblingand removing the parts of the pump.

Normally the valves 8, 22, 24 and 13 are closed. During the rotation ofthe wheel on which my invention is applied the weighted head 16'isforced outwardly by the centrifugal force produced. As the wheel travelsover irregularities in the road the vibration forces the weighted headinwardly. As the head is forced inwardly the bellows 17 expands andcreates a'vacuum in chamber 18, whereupon valve 8 opens and air enterssaid chamber through port 5, packing 25, and port 7. As the head movesoutwardly the bellows 17 and chamber 18 contract, whereupon the valve 22opens and air passes from chamber 18 through port 21 into chamber 20,the valve 8 remaining closed. When the air pressure in chamber 20becomes greater than a predetermined degree, say 80 lbs, the valve 24opens and admits airfrom said chamber through port 23 into air reservoir15, until the pressure in chamber 20 is reduced to normal. When the airpressure in reservoir 15 exceeds a predetermined degree say 90 lbs. thevalve 13 opens and air passes from the reservoir 15 through port 12 andopens the tire valve 1 and passes into the tire until the pressure insaid reservoir is reduced to normal.

Having thus explained the nature of the invention and described anoperative mannor of constructing and using the same, although .withoutattempting to set forth all of the forms in ,which it may be made, orall of the forms of its use, what is claimed 1s:--

1. In combination with a pneumatic tire valve, a pump including an aircompression chamber communicating with said tire valve. a pair ofbellows, a weighted head interposed between said bellows, means foradmitting air into one of said bellows,

means for admitting air from said bellows into the other bellows whenthe first bellows is compressed, and means for admitting air from thesecond bellows into said compression chamber.

2. A pump of the character described comprising a cap having means atone end for providing a compressing chamber and an air inlet opening atthe other end, a

reciprocable weight, air. induction and eduction members operated bysaid weight, and means controlled by the air pressure within saidmembers for controlling passage of air to said compressing chamber.

3. A pump of the character described comprising a ca havin upper andlower partitions provi ed wit openings therethrough, a weight mounted toreciprocate between said partitions, air induction and eduction membersattached to said partition' and to said weight, and means controlled byair pressure within said members for conweight and to the res ectivepartitionsyand means controlled by t e air pressure within said bellowsfor controlling the passage of air through said artitions. i

In testimon w ereof I afiix my si ature.

IXARRY C. SCHROE ER;

upper and lower

